During surgery, it is often necessary to retract tissue, especially internal tissue, to operate upon it or upon adjacent tissue. This is conventionally accomplished using forceps, or other mechanical gripping devices adapted for the purpose. Retraction or manipulation may also be accomplished by implanting a suture into the tissue, but there is a significant risk of tissue tearing even with strong, muscular tissue.
U.S. Pat. No. 4,621,619 (Sharpe) describes a plastic disposable, hand applied medical retractor for retracting flesh at the edges of an incision or aperture in the human or animal body. The retractor includes a hook for impaling flesh and a pad that has an adhesive surface that can be adhered to skin to anchor the retractor to keep flesh in a retracted position.
U.S. Pat. No. 4,899,762 (Muller) describes a combination surgical drape, dressing, and closure structure and method of use before, during, and after a surgical procedure. The dressing portion can be adhered to a patient over a surgical field and, after an incision is made, the incision can be retracted with retractors, forceps, or clamps secured to the dressing portion.
U.S. Pat. No. 5,026,389 (Thieler) describes a surgical method and apparatus for opening and closing a surgical wound. An elastic member is adhered across a patient's skin at a treatment site. An incision is made by cutting through the elastic member and through the patient's skin to permit a surgical procedure to be conducted. The incision is closed by reapproximating the patient's skin at the treatment site and by bringing the cut edges of the elastic member together and adhering a relatively inelastic sealing member over the elastic member to maintain the cut edges while the wound heals.
International Patent Publication No. WO 96/29370, published Sep. 26, 1996, describes a barrier or drug delivery system that is adherent to a tissue surface to which it is applied. Tissue can be stained with a photoinitiator, then a polymer solution or gel having added thereto a defined amount of the same or a different photoinitiator can be applied to the tissue. Exposure of light causes polymerization at the surface, providing adherence and forming a gel. The resulting polymerizable barrier materials are useful for sealing tissue surfaces and junctions against leaks of fluids. Tissue surfaces also can be adhered to each other. The adhesive qualities of the material are demonstrated in an example in which pieces of abdominal wall were excised from a euthanized rat and were clamped to a glass slide with binder clips. Polymeric material was adhered to the abdominal wall tissue. The polymer was urged away from the tissue and fractured, with portions remaining adherent to the tissue.
While the above and other disclosures describe, in some cases, useful tissue-adherent devices, there exists a need for retraction of soft internal tissues such as liver and spleen. Accordingly, it is an object of the present invention to provide a device for retraction of tissue, internally of a patient, in connection with a surgical procedure.